Sunday, 16 June 2013

List usage in Apex

List Usage in APEX:

public with sharing class ListUsage {
        
        public void listUse(){
            
            // Initialising a list
            List<String> lst = new List<String>();
            
            // Adding elemenst into list
            lst.add('ABC');
            lst.add('DEF');
            lst.add('GHI');
            lst.add('JKL');
            
            System.debug('---------Elements in the list are-------------->'+lst);
            System.debug('----------Size of the Elements are-----4-------->'+lst.size());
            System.debug('-----------Element in 2nd index--------GHI-------->'+lst[2]);

            lst.remove(1);
            System.debug('---------Elements in the list after removing are-------------->'+lst);
            System.debug('----------Size of the Elements after removing are----3--------->'+lst.size());
            
            lst.add('MNO');
            lst.add('GHI');
            lst.add('DEF');
            lst.add('1248');
            
            System.debug('---------Elements in the list after adding duplicate values are-------------->'+lst);
            System.debug('----------Size of the Elements after adding duplicate values are--------7----->'+lst.size());
            
            List<String> newlst = lst.clone();
            System.debug('---------Elements in the new list are-------------->'+newlst);
            System.debug('----------Size of the Elements in new list are-------7------>'+newlst.size());
            
            lst.clear();// removes all the elements in the list
            System.debug('-----------------List is Empty or not-------true----------->'+lst.isEmpty());
            System.debug('-----------------New List is Empty or not-------false----------->'+newlst.isEmpty());
            
            //Indexing for loop 
            for(integer i=0; i<newlst.size(); i++){
                System.debug('-----Index------->'+newlst[i]);
            }
            
            //For Each Loop
            for(String s: newlst){
                System.debug('-----For Each---------->'+s);
            }
            
            
        }
        
        
        
}

3 comments:

  1. - Ordered
    - Elastic if user add otherwise index is not elastic
    - addAll method
    - 4 nested levels overall 5 levels
    - mylist.get(0);
    - mylist.set(0,1);//add integer 1 at 0 position of the list.
    - list.sort(); //default sorting order is ascending
    - ordered
    - select options sorting 1st based on value then equal or empty then based on label
    - list smpLst = new list{1,2,3,4}

    ReplyDelete
  2. While sorting first all the capital letters will come then sort for small letters.

    ReplyDelete
  3. No limit for the size of a list. It only depends on the heap size which is 6 MB (Synchronous) and 12 MB (Asynchronous).

    ReplyDelete

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